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Progress in Natural science:Materials International 2007年第10期17卷 1226-1234页

作者： Li Qiang, Guo Fucheng and Zhou Yiyu(School of Electronic science & Engineering, National university of Defense Technology, Changsha 410073, china) School of Electronic science and Engineering National University of Defense Technology Changsha 410073 China

A new satellite to satellite tracking (SST) algorithm from Doppler-shifted frequency measurements is proposed. The estimation principle is demonstrated and the mathematic model of SST is established. The state estimation methods for a user (the cooperative case) and target satellites (the non-cooperative case) are presented based on particle swarm optimization (PSO). The Cramer-Rao lower bounds (CRLB) are deduced as well. Performance of the new algorithm is validated through computer simulations, which proved that the proposed method is effective in terms of the estimation quality compared with CRLB and superior in accuracy to the Bearings-Only (BO) method in almost all simulation cases except for the case that an enough long tracking arc-length is obtained for a user satellite.

关键词： satellite to satellite tracking (SST) Doppler-shifted frequency (DSF) Space Surveillance Network (SSN) particle swarm optimization (PSO).

Digraphs and Inclusion Intervals of Brualdi-type for Singular Values

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Acta Mathematicae Applicatae Sinica 2002年第3期18卷 471-476页

作者： Jiong-sheng Li, Kai Yang, Qing-xue WangDepartment of Mathematics, university of science and Technology of china, Hefei 230026, china Department of Mathematics University of Science and Technology of China Hefei China

A complex matrix A is said to be a matrix realization of the digraph D if D is the associated digraph of A, and A is said to have the property B if every singular value of A is contained in the union of Brualdi-type intervals. A digraph D is said to be a forcible B-digraph if every matrix realization of D has the property B. In this paper, we give a sufficient condition for a matrix to have the property B and characterize the forcible B-digraphs.

关键词： Digraph matrix realization singular value inclusion interval

Effects of various solar indices on accuracy of Earth’s thermospheric neutral density models

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science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 1120-1128页

作者： WANG HongBo1,2 & ZHAO ChangYin1 1 Purple Mountain Observatory, Chinese Academy of sciences, Nanjing 210008, china 2 Graduate university of Chinese Academy of sciences, Beijing 100049, china Purple Mountain Observatory Chinese Academy of Sciences Nanjing China Graduate university of Chinese Academy of sciences Beijing China

Four kinds of solar indices F10.7, E10.7, S10, Mg10 and four thermospheric neutral density models, i.e., CIRA72, DTM94, NRLMSISE00 and JB2006, are discussed. The CHAMP accelerometer data are used to calculate thermospheric total mass density. Based on the comparison of the model densities with CHAMP observations, the effects of various indices on the model accuracy are detected. It is found that under quiet and moderate solar conditions (F10.7200) the error’s standard deviation using E10.7 increases quickly and causes the models’ accuracy to fall down. With regard to S10, Mg10, their effects under quiet solar conditions are inconspicuous. If under active solar conditions, they can reduce the model error’s standard deviation by 5%-10%, implying that S10, Mg10 make the model error more stable. The JB2006 model, which was constructed by multi-solar-index (F10.7, S10, Mg10), is compared with DTM94 and NRLMSISE00 based on single-solar-index. It is found that JB2006’s accuracy is better than DTM94’s, and is close to NRLMSISE00 under the quiet solar condition. During the solar burst occurring on October 26, 2003, JB2006 has been in best agreement with CHAMP observations. All in all, the new indices may improve thermospheric density models’ accuracy under some special conditions. Concretely, E10.7 may reduce the average error of models and S10, Mg10 may prevent the error’s divergence.

关键词： solar radiation index CHAMP accelerometer data neutrals density model

The Direction of Marketing in E-commerce

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厦门大学学报（自然科学版） 2002年第S1期41卷 263-264页

作者： ZHANG Wu-yi 1, WEN Shu-hui 2, PENG Lan-ping 3 (1. School of Management, Huazhong university of science and Technology, Wuhan 430074, china 2. Department of Management, Kunming university of science and Technology, Kun ming 650093, china 3. Human Resource Bureau of Yunnan Province)

E-commerce is the execution of business transactio ns over the Internet. Companies conducting e-commerce can perform most of the tra nsactions which they are doing now. Most of the marketing method should coincide nt with the changes in e-commerce world. Brand ability will be depressed, but corporate identity and brand identity will be upgraded. So the enterprise should lower the cost of distribution, manufactur ing, and supplying. We can also upgrade the product value which consumer con ceded. Logistic will be core ability. The 3pl and 4pl will be used more and more often. The importance of transportation has grown with the increasing globalization as well as the growth in e-commerce. Firms should identify various transportation network design options and their relative strengths and weaknesses. They should also use methodologies for routing and scheduling deliveries in transportation network. The savings matrix and the generalized assignment methodology can be us ed to minimize the transportation cost while meeting delivery commitments to cus tomers. Information is essential to making good decisions. Information technology provid es the tools to gather information and analyze it in order to make the best deci sions. Information plays a key in every company. Information technology will be used broadly. It is a factual component on which decisions about each of the transportation, facilities, and inventory. In essence, information is the glue that holds the company to other firms, and allows it to function, making informa tion the most important firms drivers. Custom relation management, data based marketing, one to one marketing, electron ic odder system, electronic data exchange, will be used frequent. These new mark eting method is using information technology all. IT investment in program will greatly increase. The consumer can find and compare the price in every character easily on Interne t. Cost becomes the most important factor in product selecting. So the e

关键词： marketing e-commerce direction

A new species of Apocynaceae from Hainan, china

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Journal of Systematics and Evolution 2011年第2期49卷 161-161页

作者： 1 Shao-Yun HE 2 Ren-Chao ZHOU 3 Ping-Tao LI 3 Jia-Yi LIN 2 Wei WU 1 (college of Horticulture, South china agricultural university, Guangzhou 510642, china) 2 (State Key Laboratory of Biocontrol and Key Laboratory of Gene Engineering of the Ministry of Education, Sun Yat-Sen university, Guangzhou 510275, china) 3 (college of Forestry, South china agricultural university, Guangzhou 510642, china) (college of Horticulture South China Agricultural University Guangzhou 510642 China) (State Key Laboratory of Biocontrol and Key Laboratory of Gene Engineering of the Ministry of Education Sun Yat-Sen University Guangzhou 510275 China) (college of Forestry South China Agricultural University Guangzhou 510642 China)

Hoya ledongensis S. Y. He & P. T. Li, sp. nov. 乐东球兰(S2-3. Fig. 1) Type: china. Hainan: Jianfengling, on tree and rock in a montane rainforest, alt. 960 m, 2008-05-08, S. Y. He (0805081 holotype, CANT; 0805082 holo... 详细信息

关键词： IBSC china A new species of Apocynaceae from Hainan

Electrochemiluminescence from tris(2,2′-bipyridyl) ruthenium (Ⅱ) in the presence of aminocarboxylic acid co-reactants

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science china Chemistry 2009年第9期52卷 1394-1401页

作者： YIN XueBo, SHA BeiBei & HE XiWen Research Centre for Analytical sciences, college of Chemistry, Nankai university, Tianjin 300071, china Research Centre for Analytical sciences College of Chemistry Nankai University Tianjin China

Due to the highly sensitive electrochemiluminescence (ECL), tris(2,2′-bipyridyl) ruthenium(II) (Ru(bpy)32+) is often used in the field of bioarrays with the help of co-reactants. However, the generally used co-reactant, tripropylamine (TPA), is toxic, corrosive and volatile. Therefore, the search for safe, sensitive and economical co-reactants is critical. Herein, three aminocarboxylic acids, ethylenediamine-tetraacetic acid (EDTA), nitrilotriacetic acid (NTA), and 2-hydroxyethylethylene diaminetriacetic acid (HEDTA), have been investigated as potential co-reactants for promoting Ru(bpy)32+ ECL behaviour. A possible ECL mechanism is also presented. The experimental results suggested that the co-reactants have a different ECL behaviour compared to TPA, such as different pH- and surfactant-responses. The detection limits of Ru(bpy)32+ using NTA, EDTA and HEDTA as co-reactants are 1, 60 and 680 fmol·L-1, respectively. The results indicate that NTA has a much higher efficiency than TPA to excite Ru(bpy)3 2+ ECL under their own optimal conditions. NTA could be widely used in many fields because it is less toxic, corrosive and volatile than TPA. Moreover, using Ru(bpy)3 2+ ECL, a sensitive method for the detection of aminocarboxylic acids is also developed. An improvement of four orders of magnitude in detection limits is obtained for EDTA compared to the known Ru(bpy) 3 2+ chemiluminescent methods.

关键词： Ru(bpy)32+ electrochemiluminescence co-reactants aminocarboxylic acids

A NEW EXPRESSION OF X-RAY DEPTH DISTRIBUTION FUNCTION φ(pz) FOR QUANTITATIVE EDS

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电子显微学报 1991年第2期 199-200页

作者： ZHANG Renji(Tsinghua university, Beijing, china)WU Ziqin(university of science and Technology of china, Hefei, china)

In our direct standardless quantitative analysis program forEDS(1,2), the X-ray depth distribution function Φ(ρz) is based onthe improved "full diffusion" model of the electron scattering andis a stepped distribution function. From this distribution function,a quantitative relationship between the constituents of thesample and the intensities of the characteristic X-rays has beenestablished directly, and the standard samples are not required.

关键词： FOR QUANTITATIVE EDS A NEW EXPRESSION OF X-RAY DEPTH DISTRIBUTION FUNCTION pz

Vacancies and Antisites in B2 FeAl and DO_3 Fe_3Al with a Modified Analytic EAM Model

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Journal of Materials science & Technology 2001年第6期17卷 601-604页

作者： Xiaolin SHU, Wan gyu HU, Hanning XIAO and Huiqiu DENG college of Materials science and Engineering, Hunan university, Changsha 410082, china Ban gwei ZHANG International Centre of Materials Physics, Chinese Academy of sciences, S Coll. of Mat. Sci. and Eng. Hunan Univ. Changsha 410082 China

A simple modified analytic EAM model for bcc Fe and fcc Al was used to calculate the lattice constant and elastic constants of B2 FeAl and DO3 Fe3Al alloys. The formation energies of ... 详细信息

A simple modified analytic EAM model for bcc Fe and fcc Al was used to calculate the lattice constant and elastic constants of B2 FeAl and DO3 Fe3Al alloys. The formation energies of vacancy and antisite were also calculated. The present calculations are in agreement with the experimental data and the theoretical results obtained by other authors.

关键词： Al DO Fe Vacancies and Antisites in B2 FeAl and DO3 Fe3Al with a Modified Analytic EAM Model EAM

THE (ｕ＋κ)-ORBIT OF ESSENTIALLY NORMAL OPERATORS AND COMPACT PERTURBATIONS OF STRONGLY IRREDUCIBLE OPERATORS

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Chinese Annals of Mathematics,Series B 2000年第2期21卷 237-248页

作者： JIYOUQING JIANGCHUNLAN WANGZONGYAO DepartmentofMathematics JilinUniversityChangchun130023China. DepartmentofMathematics JilinUniversityChangchun130023China. DepartmentofMathematics EastChinaUniversityofScienceandTechnologyShanghai200237＂China.

Let н be a complex, separable, infinite dimensional Hilbert space, T　ε（Ｈ）. （ｕ＋Ｋ）（T） denotes the （ｕ＋ｋ）-orbit of T, i.e., （ｕ＋ｋ）（T） = {R-1TR: R is invertible and of the form unitary plus compact}. Let be an analytic and simply connected Cauchy domain in C and n ε N. A（, n） denotes the class of operators, each of which satisfies （i） T is essentially normal; （ii） σ（T） =,　ρF（T）　∩ σ（T） = ; （iii） ind （λ-T） = -n, nul （λ-T） = 0 （λ∈Ω ）. It is proved that given T1, T2 ε A（, n） and ε > 0, there exists a compact operator K with K 2）. This result generalizes a result of P. S. Guinand and L. Marcoux [6,15]. Furthermore, the authors give a character of the norm closure of （ｕ＋Ｋ）（T）, and prove that for each T ε A（, n）, there exists a compact （SI） perturbation of T whose norm can be arbitrarily small.

关键词： Essentially normal (u+k)-orbit Compact perturbation Spectrum Strongly irreducible operator